(1) Field of the Invention
The invention relates to a transfer unit for receiving in particular a porous, disk-shaped medium from a first treatment device, which has at least one upper part, the upper part having a fixing edge, which can be connected to an edge of the medium for the removal of the medium from the first treatment device.
Furthermore, the invention relates to a method for the microbiological examination and/or treatment of liquid samples, in which an upper part of a transfer unit is placed on a disk-shaped medium, which is arranged in a first lower part of a first treatment device and exposed to the liquid sample, such that a fixing edge arranged in the upper part is connected to an edge of the medium, and wherein the upper part with the connected disk-shaped medium is lifted from the first lower part and placed onto a further lower part of a further treatment device corresponding to the upper part.
(2) Description of Related Art
In the analysis of liquids and gases various treatment methods have become established which use porous media, such as filters and membranes. For example, the filtration method for the depletion and concentration of dissolved or particulate components has become established. This concentration is generally necessary, since the concentrations of the impurities are too low to carry out direct evaluations. The filtration methods are used as an initial stage for further analytical methods, such as optical evaluations, as well as for further physical and chemical reactions for signal amplification.
From DE 10 2008 005 968 A1 a nutrient medium unit and a method for receiving a filter of a filtration device are known. The nutrient medium unit is here composed of a lid, which forms the actual transfer unit, and of a lower part filled with nutrient medium. The upper part is embodied as a lid and has a fixing edge, which can be connected to an edge of the filter via an adhesive bond for the removal of the filter or medium from the filtration or treatment device.
Furthermore, from DE 10 2008 005 968 A1 a method is known for the microbiological analysis of liquid samples, in which an upper part or lid of a nutrient medium unit is placed onto a filter, embodied as a membrane filter with a fixing edge, arranged in a lower part of a filter device or treatment device. The fixing edge of the lid is in this case connected to an edge of the filter via an adhesive layer. Subsequently, the upper part with the filter is lifted from a filter support of the lower part of the filter device and placed on a surface of a nutrient medium arranged in the lower part of a nutrient medium unit, with the upper part or the lid covering the lower part, which is embodied in a dish-shaped manner.
However, the disadvantage with the known nutrient medium unit and the method, which have proven useful for classic microbiological membrane applications, in which only colonies that have formed are visually evaluated, is that no further filtration or aftertreatment can be directly added immediately after the transfer without detaching the filter again from the lid or the transfer unit. In the known method, in which the filter fixing in contact with liquid, can become detached again by itself at a later time, a further later treatment step is necessary in order to pick up the detached filter membrane again and move it to other treatments or to insert it into other units.
These disadvantages are important particularly in the case of applications which do not correspond to the classic growth of retained germs on agar, but use modern molecular-biological labeling and detection methods, regardless of whether these are methods which require a preincubation or are directly examined by labeling or intensification methods.